The Cold Spring Harbor Symposia on Quantitative Biology are held yearly at the beginning of June at the Cold Spring Harbor Laboratory, Cold Spring Harbor, New York. They bring together approximately 300-400 scientists from all over the world to present and evaluate new data and ideas in rapidly moving areas of biological research. Each year, a topic is chosen that seems to be at a stage where general and intensive scrutiny and review is needed. The Symposia always seek to bring research workers from the U.S., as well as from broad, so as to ensure the wide scope and depth of the program and to take advantage of their specific contributions. They also seek to provide outstanding younger scientists, both graduate students and post-doctoral fellows, with an opportunity to participate and communicate with more senior scientists. The Symposia also seek to have participation from women and minority scientists. The Symposia bring together scientists who use a variety of approaches, e.g., genetics, biochemistry, molecular biology, cell biology, and structural studies, to analyze problems in the area under discussion. The Leading Strand archive makes video recordings of the talks immediately available to colleagues of those who attended, while the proceedings of the Symposia are published by the Laboratory and thus made available to a wider audience than the scientists who attend the meeting. In-depth interviews with leading scientists undertaken during the Symposium provide an alternative snapshot of the state of current research. The annual Symposia will continue to be planned to further the progress of advancements in biomedical science. This proposal requests support for the 72nd Cold Spring Harbor Symposium which will focus on "Clocks and Rhythms". The meeting will address the phenomenon of biological clocks and their function and dysfunction in a variety of cells, tissues and organisms. All living organisms have internal body clocks that keep track of time, notably the dark-light cycle of the normal day. The molecular basis of these clocks has been the focus of intensive research over the past half-century. Biological rhythms depend upon the body clock, and in turn influence and are regulated by sleep and wakefulness, diet, metabolic rate, and body temperature. Disruption of these rhythms not only affects sleep patterns but also has been found to cause depression and related illness. The 2007 Cold Spring Harbor Symposium will bring together the leading experts in the field to discuss their latest findings. [unreadable] [unreadable] [unreadable]